Educators with students mainly on Chromebooks my find this report from GoGuardian of interest. GoGuardian has been able to aggregate data on 5 million student users and allows descriptive data frequency of use and trends. The greatest amount of time is spend using wt he Google tools (69%) with 62% of this time using docs and about 21% using YouTube. Quizlet was the most commonly accessed site for middle and high school students. GoGuardian also lists the most popular sites by content area which is not something I will summarize here.
Data are also provided on the proportion of students allowed to use their Chromebooks at home with some information about how the devices are used outside of school. 27%, 53%, and 57% of elementary, middle school, and high school students take their devices home. The report claims that 68% of home use is academic in nature.
It is interesting to review how these data have been evaluated. For example, Andy Losik finds the data very disturbing noting that little data are present to demonstrate students are making active use of the devices (e.g., the sites that dominate student use). It is true that only 2% of Google use is devoted to Sites so students are not building web sites. I would classify writing as active processing, but others do not classify writing in this way.